Usage of mobile devices such as smart phones, tablet personal computers, digital cameras, MP3 players, and personal digital assistants (PDAs) has increased markedly. Since various application programs may operate within mobile devices, the mobile devices may include various semiconductor devices such as a working memory (e.g., a dynamic random access memory (DRAM)), a non-volatile memory, and an application processor (AP). To improve performance and reliability of the semiconductor devices, physical variations of the semiconductor devices may be measured to control the semiconductor devices based on the measured data in real time.